Controlling device for compressors



514w Mfoz Patented J an. 27, 1920.

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R. CONRADER. CONTROLLING DEVICE FOR COMPRESSORS. I APPLICATION FILE DDEC-26, I916- 1,328,984, Patented Jan. 27, 1920.

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RUDOLPH CONRADER, 0F ERIE, PENNSYLVANIA.

CONTROLLING DEVICE FOR COMPRESSORS.

Application filed December 26, 1916.

In controlling compressors it has beencommon to control the steam supply.by a governor sensitive to speed and to pressure, commonly calledcompressor governors. It has also been common to supply suchcornpressors with an unloader or a relief device, which upon apredetermined pressure will stop the pumping action without stopping thecompressor, or will modify the pumping action so that a greater or lessamount may be pumped. During this period when the unloader is inoperation the compressor runs light or less than load. It is desirable,therefore, to have the steam supply cut down promptly so that it willdrive the compressor in accordance 'with the operation of the reliefdevice and in proper sequence to the unloading.

The invention is illustrated in the accompanying drawings as followsFigure 1 shows a side elevation of a compressor.

Fig. 2 a central section of a relief device or unloader.

Fig. 3 a central section of a compressor governor.

1 marks the compressor cylinder, 2 the intake pipe, 3 the dischargepipe, 4 the re-- ceiver, 5 the engine cylinder, 6 the steam pipe to theengine, 7 a compressor governor. 8 a pipe from the receiver to thecompressor governor, 9 a relief device and 10 a pipe from the receiverto the relief device. These features so far described may be of commonconstruction. As shown the compressor governor corresponds to, agovernor patented by me Nov. 22nd. 1904, #775,391 and the relief devicecorresponds to a relief device patented by me June 28th, 1910, #962,551.The relief device com- Specification of Letters Patent.

Patented Jan. 27, 1920.

Serial No. 138,747.

prises the valve body 11- with the passage 12 therein, the Valve 13opening and closing the passage 12. The valve is carried by a stem 14terminating in a head 15. A spring 16 is tensioned between the head 15and a yoke 15 and tends to hold the valve in open position. The head 15is seated on the piston 17. The piston 17 operates in a cylinder 18. Thecylinder 18 is mounted in an extension 19 on the valve body. Thecylinder communicates by way of a. pipe 20 with the intensifying chamber21. A controlling passage 22 leads to the chamber 21 and this iscontrolled by a needle valve 23. The needle valve 23 is carried by apiston 24. The piston 24 is arranged in a cylinder 25. A spring 24 tendsto close the needle valve. The pipe 10 leads to the chamber 21 so thatit is subjected to receiver pressure. This device operates in the man-'ner described in my former patent. When the pressure reaches apredetermined point, it overcomes the spring 24 and moves the piston 24opening the valve 23. The air passes into the chamber 21 and from thenceinto the cylinder 18. When the pressure is reduced, the valve 23 closesand the-air in the chamber 21 and cylinder exhaust through a minuteopening 26. The unloader or relief device operates differently dependingon the end nearest the intake. If the air passes through from the rightto left, as shown in Fig. 2, the valve 13 closes gradually. Where thisis the operation. the leak 26 is such that operating in relation to thevalve 23 there is a wide range of pressure on thepiston and a niceregulation so that the relief device here graduates the pumping action.If the air passes from the left to right at the intake, as soon as thevalve 13 starts to close. it completely closes by reason of the aircurrent or action of the air upon the valve itself. the air passingthrough a spider 1.) by means of the opening 27 to facilitate thispurpose. This action is fully described in my patent above referred to.r

The compressor governor has the valve bodv 28 which is connected on thesteam pipe 6, the valve 29 operating therein. A stem 30 extends from thevalve 29 to the step bearing 31. A spindle 32 extends from the stepbearing 31 to the cross head 33. Links 34 connect the cross head withthe weights 35. The weights are pivoted on the carrier 36 by means ofpins The carrier is journaled in a bearing 37 in the frame 38. A gear 39on the lower end of the bearing meshes a gear 40 on the shaft 41. Theshaft 41 is mounted in a bearing 42 and a pulley 43 is arranged to bedriven from the engine. A lever 44 is pivoted on a pin 45, the pin 45being mounted in the frame. The end 46 of the lever 44 operates in aslotin the step bearing 31. The opposite end 47 of the lever is secured to arod 48. The rod 48 extends upwardly through a nut-49 arranged in theupper end of a movable frame 49. A spring 50 is tensioned between thenut 49 and a shoulder 48 at the lower end of the rod.

This forms the centripetal element of the governor. The frame is held inits lower position up to a certain air pressure by the springs 51, thesesprings being secured to the arms 52 on the frame and to the arms 53extending each side of the pressure cylinder 54. A stem 55 extends fromthe frame into the cylinder and operates against a piston 56. Air isadmitted through the passage 57 from the chamber 58 and to the chamber58 by the passage 59. The passage 59 is controlled by a needle valve 60.The needle valve is carried by a piston 61 which operates in a cylinder62. A stem 63 extends from the piston and rests against a lever 64. Thelever is pivoted on a pin 65 and has an arm 66 on which a weight 66 isarranged. The weighted lever, therefore, opposes the movement of thepiston. It is also opposed by a spring 67. The air is admitted to thecylinder 62 from the-pi e 8 and when the pressure reaches a cer ainpoint, it moves the piston so as to open the needle valve and as the airgoes into the chamber 58, the piston 56 is gradually moved upwardly,thus changing the centripetal element, and changing the normal speed ofthe governor, bringing it down to the lower speeds in the control of thecompressor.

In order to intensify the change of pressure in the receiver a leak 68is provided in the chamber 58 and the relative proportions between theleak 68 and the opening formed by the valve 60 make a wide range invariation in pressure with a slight range of variation in the receiver.This is fully explained in my patent above referred to. So far theseparts are as heretofore constructed.

It is desirable to bring the governor valve to a predetermined positionwhen the unloader operates, or to have it operate in exact accordancewith the unloader so that the steam will be introduced in accordancewith the load. I accomplish this by the following mechanism: Anextension'69 is ar ranged on the lever 44. The end of this -leverextends into a pocket or strap 70 at the upper end of the stem 71. Thestem 71 is secured to a piston 72. The piston 72 operates in a cylinder73. A pipe 74 connects the cylinder 73 with the intake 2 between therelief device or unloader and the compressor cylinder.

Vhen the unloader or relief device operates it creates a vacuum orpartial vacuum in the intake 2. This is communicated through'the pipe 74with the cylinder 73, thus reducing the pressure above the piston. Theair pressure below the piston then moves it upwardly. This carries thestem 71 and with it the outer end of the lever 44 upwardly. This closesthe valve. Where the unloader is set to operate abruptly this movementtakes place abruptly but where it is set to regulate, this movement maybe regulated accordingly. lVhen the unloader is thrown out so that thevalve 13 is open the air in the intake approximates atmosphericpressure.- The springs 50 of the governor immediately return the piston72 to some intermediate position.

In order to accurately. adjust the minimum opening to which the valvemay be moved I form the screw 76 as an extension of the stem 71 andplace a nut 77 on this screw. This nut may be adjusted so that in theupward movement of the piston it contacts the end of the cylinder andthus forms a stop at the desired position.

In order to retard abrupt actions I prefer to provide a small openingbetween the pipe 74 and the cylinder 73. This opening while large enoughto communicate promptly any variations of pressure in the intake pipegives to the cylinder more or less of a dash pot effect for setting thegovernor.

. What I claim as new is 1. In a controlling device for compressors, thecombinationbf a compressor governor comprising a valve, a speedsensitive element influencing the valve, and a fluid actuated pressuredevice influencing the valve, with a compressor intake, a relief deviceon the intake, a motor acting on said valve, and a connection betweenthe intake and the motor whereby the governor is influenced inaccordance with the operation of the relief device.

2. In a controlling device for compressors, the combination of acompressor governor comprising a valve, a speed sensitive elementinfluencing the valve, and a fluid actuated pressure device influencingthe valve, with a compressor intake, a relief device on the intake, amotor acting on said valve to move it to a minimum opening. and aconnection between the intake and the motor whereby the governor isinfluenced in accordance with the operation of the relief device.

3. In a controlling device for compressors, the combination of acompressor governor, comprising a valve, a speed sensitive element, anda fluid actuated pressure element influencing the valve with a reliefdevice, a

motor acting on said valve, and a connection leading from the motorcontrolled by the relief device.

' 4. In a controlling device for compressors, the combination of acompressor governor,

.comprising a valve, a speed sensitive element, and a fluid actuatedpressure element influencing the valve, with a relief device,'a motoracting on said valve, a connection leading from the motor controlled bythe relief device, and means for retarding the action of the motor.

5. In a controlling device for compressors, the combination of acompressor governor, comprising a valve, a speed sensitive element, anda fluid actuated pressure element influencing the" valve with-a reliefdevice, a motor acting on said valve, a connection leading from themotor controlled by the re lief device and means for retarding theaction of the motor, comprising a restricted opening through which fluidmoves as the motor is moved.

6. In a controlling device for compressors, the combination of acompressor governor comprising a valve, a speed sensitive elementinfluencing the valve, and a fluid actuated pressure device influencingthe valve, with a compressor intake, a relief device on the intake, amotor acting on said valve, a connection between the intake and themotor whereby the governor is influenced in accordance with theoperation of the relief device and means for retarding the movement ofair between the intake and the motor.

7. In a controlling device for compressors, the combination of acompressor governor comprising a valve, a speed sensitive elementinfluencing the valve, and a fluid actuated pressure device influencingthe valve,

with a compressor intake, a relief device on the intake, a motor actingon said valve, a connection between the intake and the motor whereby thegovernor is influenced in ac-- cordance with the operation of the reliefdevice, and meansfor retarding the movement of air between theintake andthe motor, comprising a restricted opening through which fluid moves asthe motor is moved.

In testimony whereof I have hereunto set my hand.

RUDOLPH CONRADER.

